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Related papers: Dynamical collapse for photons

200 papers

Intense light with frequencies above typical atomic or molecular ionization potentials as provided by free-electron lasers couples many photons into extended targets such as clusters and biomolecules. This implies, in contrast to…

Atomic and Molecular Clusters · Physics 2011-05-25 Christian Gnodtke , Ulf Saalmann , Jan-Michael Rost

We derive a redshift drift formula within the framework of varying speed of light (VSL) theory using the specific ansatz for the variability of $c(t) = c_0 a^n(t)$. We show that negative values of the parameter $n$, which correspond to…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-26 Adam Balcerzak , Mariusz P. Dabrowski

The evolution of the virial overdensity $\Delta_{\rm vir}$ for $\Lambda$CDM and seven dynamical dark-energy models is investigated in the extended spherical collapse model (SCM). Here the virialization process is naturally achieved by…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-10 Francesco Pace , Carlo Schimd , David F. Mota , Antonino Del Popolo

We compute the critical density of collapse for spherically symmetric overdensities in a class of f(R) modified gravity models. For the first time we evolve the Einstein, scalar field and non-linear fluid equations, making the minimal…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-26 Michael Kopp , Stephen A. Appleby , Ixandra Achitouv , Jochen Weller

The Dead Leaves Model (DLM) provides a random tessellation of $d$-space, representing the visible portions of fallen leaves on the ground when $d=2$. For $d=1$, we establish formulae for the intensity, two-point correlations, and asymptotic…

Probability · Mathematics 2020-04-14 Mathew D. Penrose

The evolution of a composite closed system using the integral wave equation with the kernel in the form of path integral is considered. It is supposed that a quantum particle is a subsystem of this system. The evolution of the reduced…

Quantum Physics · Physics 2017-08-30 A. Yu. Samarin

By photo-transmutation of leptons we mean photon-lepton reactions of the following type: $\gamma l_\alpha \longrightarrow \gamma l_\beta$ with $l_\alpha \neq l_\beta$, occurring as a consequence of the lepton mass matrix changing its…

High Energy Physics - Phenomenology · Physics 2011-02-11 J Bordes , HM Chan , J Faridani , ST Tsou

The Liouville equation governing the evolution of the density matrix for an atomic/molecular system is expressed in terms of a commutator between the density matrix and the Hamiltonian, along with terms that account for decay and…

Quantum Physics · Physics 2015-06-17 M. S. Shahriar , Ye Wang , Subramanian Krishnamurthy , Y. Tu , G. S. Pati , S. Tseng

Using thermal field theory, we derive simple analytic expressions for the spectral density of photons in degenerate QED plasmas, without assuming the usual non or ultra-relativistic limit. We recover the standard results in both cases.…

High Energy Physics - Phenomenology · Physics 2011-05-23 T. Altherr , E. Petitgirard , T. del Rio Gaztelurrutia

This talk was in response to the conference injunction to present "one bold but half-baked idea that you have been thinking about recently.. .". After a brief introduction to the ideas and formalism of the CSL theory of dynamical wave…

Quantum Physics · Physics 2007-10-03 Philip Pearle

A high energy power law is a common feature in the spectra of many astrophysical objects. We show that the photons in a relativistic plasma with a variable Lorentz factor go through repeated scattering with electrons to gain energy. The…

High Energy Astrophysical Phenomena · Physics 2023-02-01 Mukesh K. Vyas , Asaf Pe'er

We develop a projection imaging technique to study ultracold plasma dynamics. We image the charged particle spatial distributions by extraction with a high-voltage pulse onto a position-sensitive detector. Measuring the 2D width of the ion…

Plasma Physics · Physics 2009-11-13 X. L. Zhang , R. S. Fletcher , S. L. Rolston

As synthetic data proliferates across the Internet, it is often reused to train successive generations of generative models. This creates a ``self-consuming loop" that can lead to training instability or \textit{model collapse}. Common…

Machine Learning · Computer Science 2025-11-18 Zhongteng Cai , Yaxuan Wang , Yang Liu , Xueru Zhang

We have investigated the effect of spatial resolution on determining pencil-beam like velocity widths and column densities in galaxies. Three 21-cm datasets are used, the HIPASS galaxy catalogue, a subset of HIPASS galaxies with ATCA maps…

Astrophysics · Physics 2007-05-23 Emma V. Ryan-Weber , Lister Staveley-Smith , Rachel L. Webster

The "Breakthrough Starshot" program is planning to send transrelativistic probes to travel to nearby stellar systems within decades. Since the probe velocity is designed to be a good fraction of the light speed, \citet{zha18} recently…

High Energy Astrophysical Phenomena · Physics 2019-10-09 Yuan-Pei Yang , Jin-Ping Zhu , Bing Zhang

A model of Lorentz invariant random fluctuations in photon polarization is presented. The effects are frequency dependent and affect the polarization of photons as they propagate through space. We test for this effect by confronting the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Carlo Contaldi , Fay Dowker , Lydia Philpott

We review the argument that latent image formation is a measurement in which the state vector collapses, requiring an enhanced noise parameter in objective reduction models. Tentative observation of a residual noise at this level, plus…

Quantum Physics · Physics 2019-10-23 Stephen L. Adler

Photons traveling cosmological distances through the inhomogeneous Universe experience a great variation in their in-medium induced effective mass. Using the EAGLE suite of hydrodynamical simulations, we infer the free electron distribution…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Andres Aramburo Garcia , Kyrylo Bondarenko , Sylvia Ploeckinger , Josef Pradler , Anastasia Sokolenko

This paper presents an information-theoretic view of how an observer within a quantum system will perceive his world. It is argued that because of the indistinguishability of quantum particles, a coherent state will appear to an observer…

Astrophysics · Physics 2007-05-23 Subhash Kak

The S-matrix element and the cross section of the laser-assisted nuclear photoeffect are recalculated in a gauge invariant manner taking into account the effect of the Coulomb field of the remainder nucleus. The \gamma-photon energy…

Nuclear Theory · Physics 2013-03-07 Péter Kálmán , Dániel P. Kis , Tamás Keszthelyi
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